A5040649107- Soil Carbon and Nitrogen Dynamics
- Mycorrhizal Fungi and Plant Interactions
- Forest Ecology and Biodiversity Studies
- Climate change and permafrost
- Soil and Water Nutrient Dynamics
- Cryospheric studies and observations
- Ecology and Vegetation Dynamics Studies
- Atmospheric and Environmental Gas Dynamics
- Microbial Community Ecology and Physiology
- Hydrology and Watershed Management Studies
- Fire effects on ecosystems
- Forest ecology and management
- Remote Sensing and LiDAR Applications
- Geology and Paleoclimatology Research
- Plant Water Relations and Carbon Dynamics
- Tree-ring climate responses
- Seedling growth and survival studies
- Peatlands and Wetlands Ecology
- Climate Change and Health Impacts
- Arctic and Antarctic ice dynamics
- African Botany and Ecology Studies
- Soil erosion and sediment transport
- Radioactivity and Radon Measurements
- Leaf Properties and Growth Measurement
- Botany and Plant Ecology Studies
University of Minnesota
2017-2025
Northern Arizona University
2022-2025
University of Georgia
2018
SUNY College of Environmental Science and Forestry
2015-2016
State University of New York
2016
Purchase College
2015
Associations between soil minerals and microbially derived organic matter (often referred to as mineral-associated or MAOM) form a large pool of slowly cycling carbon (C). The rhizosphere, immediately adjacent roots, is thought control the spatial extent MAOM formation because it dominant entry point new C inputs soil. However, emphasis on rhizosphere implicitly assumes that microbial redistribution into bulk (non-rhizosphere) soils minimal. We question this assumption, arguing extensive...
Abstract Tundra and boreal ecosystems encompass the northern circumpolar permafrost region are experiencing rapid environmental change with important implications for global carbon (C) budget. We analysed multi-decadal time series containing 302 annual estimates of dioxide (CO 2 ) flux across 70 non-permafrost ecosystems, 672 summer CO 181 ecosystems. find an increase in sink but not despite similar increases uptake. Thus, recent non-growing-season losses have substantially impacted balance...
Abstract The Arctic–Boreal Zone is rapidly warming, impacting its large soil carbon stocks. Here we use a new compilation of terrestrial ecosystem CO 2 fluxes, geospatial datasets and random forest models to show that although the was overall an increasing sink from 2001 2020 (mean ± standard deviation in net exchange, −548 140 Tg C yr −1 ; trend, −14 P < 0.001), more than 30% region source. Tundra regions may have already started function on average as sources, demonstrating shift...
Abstract Tropical cyclones (i.e. hurricanes, typhoons) cause large pulse fluxes of leaves that have not undergone senescence green litter) to forest soils, with consequences for biogeochemical cycling. Energy and mineral nutrient concentrations litter are higher than the naturally senesced litter, likely affecting rates decomposition release, as well structure composition detrital food webs, but these effects been quantified. During typhoon ‘Hagubit’, we collected from three common urban...
Previous studies have attempted to link foliar resorption of nitrogen and phosphorus their. respective availabilities in soil, with mixed results. Based on resource optimization theory, we hypothesized that the one element could be driven by availability another element. We tested various measures soil N P as predictors six tree species 18 plots across stands at Bartlett Experimental Forest, New Hampshire, USA. Phosphorus efficiency (P < 0.01) proficiency = increased content. 30 cm depth,...
Summary Interactions between symbiotic ectomycorrhizal (EM) and free‐living saprotrophs can result in significant deceleration of leaf litter decomposition. While this phenomenon is widely cited, its generality remains unclear, as both the direction magnitude EM fungal effects on decomposition have been shown to vary among studies. Here we explicitly examine how contrasting types communities may lead differential carbon (C) nitrogen (N) cycling. Specifically, measured response soil nutrient...
Abstract Downed coarse woody debris, also known as detritus or downed dead wood, is challenging to estimate for many reasons, including irregular shapes, multiple stages of decay, and the difficulty identifying species. In addition, some properties are commonly not measured, such wood density carbon concentration. As a result, there have been few previous evaluations uncertainty in estimates which necessary analysis interpretation data. To address this shortcoming, we quantified...
ABSTRACT Microbial necromass contributes significantly to both soil carbon (C) persistence and ecosystem nitrogen (N) availability, but quantitative estimates of C N movement from into soils decomposer communities are lacking. Additionally, while melanin is known slow fungal decomposition, how it influences microbial acquisition as well elemental release remains unclear. Here, we tracked decomposition isotopically labeled low high measured 13 15 accumulation in surrounding over 77 d a...
Abstract Synthesis research in ecology and environmental science improves understanding, advances theory, identifies priorities, supports management strategies by linking data, ideas, tools. Accelerating challenges increases the need to focus synthesis on most pressing questions. To leverage input from broader community, we convened a virtual workshop with participants many countries disciplines examine how where can address key questions themes coming decade. Seven priority topics emerged:...
Summary In theory, ectomycorrhizal (EM) and saprotrophic fungi compete for nitrogen (N) found in soil organic matter. However, both positive negative effects of EM on decomposition have been observed across systems, with opposing implications carbon (C) storage. The conditions driving the context dependency fungal guild interactions remain poorly understood, which has limited our ability to predict biogeochemical cycling at regional global spatial scales. To address this knowledge gap, we...
Abstract Fungi represent a rapidly cycling pool of carbon (C) and nitrogen (N) in soils. Understanding how this impacts soil nutrient availability organic matter fluxes is hindered by uncertainty regarding the dynamics drivers fungal necromass decomposition. Here we assessed generality common models for predicting mass loss during decomposition linked resulting parameters to substrate chemistry. We decomposed 28 different types laboratory microcosms over 90‐day period, measuring on all...
The below-ground growing season often extends beyond the above-ground in tundra ecosystems and as climate warms, shifts seasons are expected. However, we do not yet know to what extent, when where asynchrony above- phenology occurs whether variation is driven by local vegetation communities or spatial microclimate. Here, combined plant metrics compare relative timings magnitudes of leaf fine-root growth senescence across microclimates at five sites Arctic alpine biome. We observed...
Permafrost thaw causes the seasonally thawed active layer to deepen, causing Arctic shift toward carbon release as soil organic matter becomes susceptible decomposition. Ground subsidence initiated by ice loss can cause these soils collapse abruptly, rapidly shifting moisture microtopography changes and also accelerating nutrient mobilization. The uncertainty of trajectories during makes it difficult predict role abrupt in suppressing or exacerbating losses. In this study, we investigated...
The permafrost region has accumulated organic carbon in cold and waterlogged soils over thousands of years now contains three times as much the atmosphere. Global warming is degrading with potential to accelerate climate change increased microbial decomposition releases soil greenhouse gases. A 19-year time series ecosystem respiration radiocarbon from Alaska provides long-term insight into changing dynamics a warmer world. Nine per cent 23% observations had values more than 50‰ lower...
Ecosystem budgets of water and elements can be difficult to estimate are often unreplicated, making it challenging provide confidence in estimates ecosystem pools fluxes. We conducted a survey learn about current practices reporting uncertainties precipitation, streamflow, soils, vegetation. Uncertainty derives from natural variation, which is commonly characterized by replicate samples, imperfect knowledge, includes measurement error model (model fit selection). asked questions whether...
Abstract Below‐ground litter decomposition represents an important source of the limiting nutrients nitrogen (N) and phosphorus (P) to forest soils, but roots also immobilize these during process. Despite clear implications for soil fertility, rates drivers nutrient immobilization release (as percent increase decrease initial pool) from root remain poorly understood, especially in coarse (>2 mm diameter). To address this gap, we conducted a 7‐year field experiment using three species,...
Humans have fundamentally altered the cycling of multiple elements on a global scale. These changes impact structure and function terrestrial aquatic ecosystems, with many implications for human health. Most prior studies linking biogeochemical to health evaluated effects single in isolation. However, biological shifts concentration element often depend its relative balance other elements. This among is focus ecological stoichiometry, which highlights importance elemental ratios across all...
Abstract Designs for litterfall sampling can be improved by understanding the sources of uncertainty in mass and nutrient concentration. We compared coefficient variation leaf concentrations (nitrogen, phosphorus, calcium, magnesium, potassium) at different spatial scales across years six northern hardwood species from 23 stands White Mountains New Hampshire, USA . Stands with steeper slopes ( P = 0.01), higher elevations 0.05), more westerly aspect 0.002) had interannual litter mass,...
Abstract Monitoring solutes in precipitation inputs and stream water exports at small watersheds has greatly advanced our understanding of biogeochemical cycling. Surprisingly, although to outputs from ecosystems are instrumental sources sinks nutrients other elements, uncertainty these fluxes is rarely reported ecosystem budgets. We illustrate error propagation input–output budgets by comparing the net hydrologic flux Ca a harvested reference watershed Hubbard Brook Experimental Forest, New...